The Number: $60 Billion

When Groupon went public, in 2011, it was valued at $13 billion. Today, in the wake of the C.E.O. Andrew Mason’s ouster, it’s worth $3.1 billion.

Since the tech bubble burst, six tech firms have been valued at more than $5 billion when they went public—Facebook, Google, Groupon, MetroPCS, Yandex (a Russian search company), and Zynga. Of those companies, only Google has increased in value since its I.P.O. The others have diminished in value by an aggregate $60 billion. Facebook has done the worst: it’s worth $40 billion less than on the day it had its I.P.O.

Twitter, which is still privately held, made news this past week when some investors pegged it as a $10 billion company. They will inevitably join this group of huge I.P.O.s. Whether they’ll become a Google or a Groupon remains to be seen.